The invention relates generally to turbine technology. More particularly, the invention relates to a steam turbine having exhaust enthalpic condition control and a related method.
Two types of steam turbines used in industry are a condensing steam turbine and a non-condensing steam turbine. A condensing steam turbine exhausts steam in a partly condensed state, while in a non-condensing steam turbine steam is pulled from various locations and used for other industrial applications such as preheating water boilers, etc. Valves may control steam extracted from a non-condensing steam turbine. Non-condensing steam turbines are typically used in industrial applications where there is a need to have steam at specific pressure and temperature conditions for other industrial applications. Extraction points can be located at any point in the steam path that provides the necessary steam conditions.
Steam for industrial applications can be obtained from turbine extractions or from the turbine exhaust. Steam condition requirements vary from one customer to the other. Consequently, each steam turbine may require specific modifications of the steam turbine structure to achieve the desired enthalpic conditions for the exhaust, which is cumbersome and expensive. Since there are only so many models of steam turbine that a manufacturer can reasonably produce, there may be instances where use of exhaust steam for other industrial applications may not be possible while still meeting other requirements for the steam turbine.